Historically, mattresses have used metallic springs encased in layers of upholstery to support and distribute the weight of a user. One alternative to spring-based mattresses are mattresses with layers of foam that accomplish the same purpose of supporting the user. Another alternative is air-filled or water-filled chambers or bladders in a supporting structure. An advantage of air-filled type mattresses is that a user can operate an air pump to adjust the amount of air in the chamber to adjust the support provided by the mattress.